For the industrial treatment of objects, in particular vehicle bodies or the parts thereof, in which large piece numbers have to be processed, preference is given to the use of devices of the type stated at the outset in which the objects can be guided continuously or discontinuously through the treatment chamber by means of a conveying appliance. Such devices have a high capacity and are well suited to being incorporated into a production line. Treatment can be painting or drying, for example.
The walls of the treatment chamber separate the latter from an outer region and, in particular, prevent any treatment medium applied and/or heat from escaping from the treatment chamber into said outer region. The term “wall” can be taken to mean any parts of a casing or of a housing of the treatment chamber, e.g. a side wall, a bottom wall or a top wall. A wall can, for example, also be a wall of a housing of some other subassembly which is arranged in the treatment chamber. For example, the wall can belong to the housing of a cover for a guide track on which a working unit, e.g. an application robot, is moved.
The walls of the treatment chamber and the sealing thereof are intended, for example, to prevent liquids, gases and/or vapors of the kind that may be present in painting or drying booths, for example, from escaping from the treatment chamber. In painting booths, there is also, for example, the intention of keeping clouds of liquid or powder away from the environment of the treatment chamber. The intention is also, for example, to prevent dirt from penetrating into the interior of the treatment chamber from outside.
In the present context, the term “sealing” does not necessarily imply hermetic sealing of the adjacent regions, i.e. the treatment chamber and the outer region. The aim is to achieve acceptable residual leakage, which is appropriate to requirements and may be different from one plant to another.
A working unit can be, for example, a treatment unit and, in particular, a multi-axis application or painting robot, which guides an application unit, e.g. a spray gun or a rotary atomizer, at an end of a robot arm which is situated in the treatment chamber. Said working unit can also be, for example, a conveying appliance and can have a support arm for supporting objects, which is situated in the treatment chamber. Drive components of the conveying appliance, from which contaminants may usually originate, are advantageously arranged in the outer region away from the treatment chamber.
Known devices of the type stated at the outset are often of complex construction and are fault-prone, especially in respect of the means provided for sealing the opening.
EP 1 277 521 A2, for example, discloses a covering band for a housing opening of a coating installation, wherein carriages for moving coating devices are provided on a rail structure of the coating installation in such a way that they can be moved along a slot-type housing opening. There, the housing opening is covered by a stationary covering band, which is fastened on the housing and which is lifted away from the housing opening by a lifting device on the carriage during movement of the carriages. In the case of this stationary covering band, cleaning of the covering band contaminated with impurities from the treatment chamber can be accomplished only from the same side as the treatment chamber.
Another covering assembly for a booth, in particular a painting booth, is described in DE 10 2012 211 135 A1. There, the covering assembly has a multiplicity of seal elements for a slot-shaped opening extending in a longitudinal direction in a wall of a booth, said seal elements being arranged in succession in the longitudinal direction, covering the opening. The seal elements are mounted on a holding device fixed relative to the wall, wherein the seal elements are mounted pivotably on the holding device. Here, the mechanical complexity is very high.